Rat-hole swivel wrench



June 8, 1943. J. E. REED RAT-HOLE SWIVEL WRENCH Filed April 14, 1941Patented June 8, 1943 UNITED STATE QFFICE Claims.

This invention is a means and method for making and breaking screwjoints between an elevator kelly in a well rig and what is known as asingle in a rat-hole in the rig platform.

A single as here used means one section or piece of a drill stem orother well string structure a multiplicity of which singles go to makeup the stem or string. Commonly, a stock of singles may lay horizontallyon the rig wharf, or stock deck and one single at a time is pulled by acatline to a nearly vertical position over the mouth of a rat-hole whichis a hole through the derrick floor and deeply into the ground at ashort distance from the well hole being drilled at the rig. The singleis then lowered into the rathole and its upper end is suitably held sothat the lower end of the kelly can be lowered into juxtaposition withthe upper, pin receiving box end of the single and then, usually bymeans of ropes and tongs, the kelly screw pin is screwed into the box ofthe single held in the rat-hole. This last performance is tedious andtime taking, and requires roping and rope handling; that is, getting outand putting away.

When breaking down a long drill stem or other string, derrick sections,each as long as two or three singles, are unscrewed one after the otherand then stood on end in the derrick tower until such time as use of thestands will no longer be needed. Then each section is broken into itscomponent singles so that these can be shifted out of the towe and laidon the wharf to be hauled away or stored.

It is an object of the present invention to provide a means and a methodfor the expeditious connecting up or the knocking down of singles, ofstem or pipe, and to eliminate the usual cat-line or roping in making orbreaking the screw joints.

It is an object of the invention to provide a simple, practical, lowcost, substantial and highly effective swivel wrench for rat-hole use.

Another object of the invention is to provide a self-feeding wrench,that is, one in which there is a rotary gripping means having anautomatic function of feeding one part of the coupling being made uponto the other part.

Further, an object is to provide a unitary power-plant, swivel-function,rat-hole wrench.

And further, an object of the invention is to provide in combination, arat-holed derrick floor and a swivel, single wrench.

The invention consists in certain advancements in this art as set forthin the ensuing disclosure and having, with the above, additional objectsand advantages as hereinafter developed, and

whose constructions, combinations, and details of means and the mannerof operation, and the method, will be made manifest in the followingdescription of the herewith illustrative apparatus; it being understoodthat modifications, variations and adaptations may be resorted to withinthe scope, principle and spirit of the inven tion as it is moreparticularly claimed presently.

Figure l is a diagram of a rig having a rat-hole for singles and withwhich the instant Wrench is combined.

Figure 2 is a plan of the self-powered wrench, engaging an introducedsingle, shown in crosssection.

Figure 3v is a side elevation and partial axial section of the wrench,in normal empty position of parts.

The derrick floor 2 is provided with the usual central rotary table 3over the hole being drilled, or finished well, and oil to one side ofthe table there is shown a slightly inclined pipe or'casing 4 whichforms or lines a rat-hole in which a single (drill or other section) Sis here disclosed suspended by the wrench B of the present invention.

The wrench includes a suitably shaped basal flange I with a central,bottom face, upwardly converged orifice lip .or guide 8 leading to abarrel 9 of which the base I is a rigid part. I

In the bottom of the barrel is a suitable ball'race ID for a set ofballs I I carrying a running race I2 fixed to a superj'acent ring I3which here forms a worm-gear I I and is fixed to a ring I5 inturned froma running cylinder I5a concentric in the barrel 9. The rim of the barrelhas a retainer flange I6 overhanging the cylinder rim to keep thecylinder down.

A series of posts I I is fixed in the ring I5 and each post has acompression spring I8. Supported on the upper ends of the springs is nannular basket I9 with opposite, lateral lugs 24) overhung by the barrelflange I 6 and pressed to it by the set of springs. The basket has aconical bore for the reception of a complementary set of slips 2| whosebore teeth 22 are adapted to bite onto a complementary size drill stemelement or other desired element, here called a single, while arrangedin the rat-hole. being lowered through the wrench basket I9 the slipsare first withdrawn so that the bottom or pin-screw end of the singlecan be easily stabbed into the rat-hole. The single is then lowered, asby a cat-line, until the upper or box-thread end of the single is justabove the wrench basket and then the slips are inserted into the basketto grip the body of the single and hold it suspended in the When asingle S is rat-hole; the springs still holding the basket up to theretainer IS.

The slips 2| are here shown as hollow, and

about a half a circle in arcuate length and have free drop-handles 2 lain their tops.

In making up a connection between the lower or pin-screw end of a kellyK, while this is suspended by the rig elevator, the pin end is swungover into alignment with the box end of the wrench supported single Sand then the kelly is gradually lowered and the pin is stabbed into thepresented box of the single S. The added partial load of the kellycauses the single S and the basket with the slips to recede and pressthe lugs 20 down in channelways 20a provided therefor in the innercylinder 15a; the lugs therefore interkey the basket and the cylinderI5a for co-rotation.

The cylinder and its basket may now be rotated either manually or bysome prime mover such as a small power plant 25 having a shaft 26carrying and driving a screw or worm 26 engaging the large drive wheelfixed to the cylinder.

A feature of the invention is that, as the slip basket is rotated whilegripping a single S, and has been repressed by the stabbing of the Kellypin into the box end of the single S, the springs l8 run the boxupwardly on the Kelly pin if the rotation of the basket is to theright-hand (looking up) the kelly being held suspended by the elevator.After the joint has been thus made up tongs are applied to the kelly andto the box so that a heavy torque may be applied to the box to clinch upthe joint very tightly. The single is then released from the bite of theslips and these are pulled from the basket and the elevator is operatedto elevate the now joined single and kelly.

Thus the kelly is never disconnected from the elevator and is itselfmade of service in the making up of a joint and in pulling the single Sfrom the rat hole and swinging it to the well or hole being drilled. Theslip basket is used at the top of the rat hole to suspend the insertedsingle S and it is used to screw the single to the Kelly pin and nospecial or secondary elevator or other apparatus is used after thesingle has once been cat-lined in from the wharf and set in the rathole.

It will be seen from the above how easy it will be to reverse theprocedure and quickly break down stands of stem or pipe, racked uprightin a tower, into individual pieces so that they may be readily cat-linedout to the wharf.

It has been found by actual practice that a great deal of time has beensaved by the tool and method here disclosed in the jointing of singlesto make up a drill stem of only a thousand feet in length, and its valuein the handling of strings of from five to ten thousands of feet lengthwill be apparent at once.

Compactness, simplicity and low cost of construction and of operationare meritorious features of the swivel wrench of this invention.

What is claimed is:

1. A unitary, well-rig, string joint making and breaking apparatusincluding a prime motored frame or mount, a swivelled slip basketyieldably supported on said mount, and a drive connection between themotor and the basket for rotating the basket.

2. The apparatus ofclaim 1, the mount having a rotary carrier on whichthe basket is splined, and a set of springs on the carrier for yieldablysupporting the basket whereby to automatically advance the basket inmaking up a screw joint of string members.

3. A rat-hole swivel wrench, for well drilling operations, including amount fixable above the rat-hole, a swivelled slip basket yieldably androtatively supported in the mount for suspending a drill string sectionin the rat-hole, and power means for rotating the yieldable basket toscrew together or to unscrew meeting drill sections.

4. A well drilling tool rat-hole swivel wrench for screwing up orunscrewing threaded joints of drill string sections and which includes amount fixable above the rat-hole, a slip basket swivelled on the mountto suspend a drill section in the said rat-hole and being cushioned toprovide for axial movement as to the mount, and means keyed to thebasket and operative to rotate the basket whereby to screw on or toscrew off the suspended section as to an upper juxtaposed companiondrill string part.

5. A rat-hole wrench, for receiving well drilling tool parts, includinga mount fixable in alinement with the rat-hole, a rotary carrier on themount, a slip basket splined on the carrier for co-rotation therewith,and a spring means whereby the basket is yieldably supported on thecarrier for axial shift under the load of an applied drill tool part;whereby as the carrier is rotated a thread joint can be opened or closedas between the tool part in the basket and an upper, adjacent tool part.

JOHN E. REED.

